Fluorescent lamp socket



Sept. 11, 1951 R. P. ROSEN 2,557,731

FLUORESCENT LAMP SOCKET Filed Nov. 20, 1946 ATTORNEY.

i atenteci Sept. 11

UNITED STATES PATENT OFFICE 2,567,731 FLUORESCENT LAMP socKET Ruben P. Rose'n, Philadelphia; Pa, assignor to Progress Manufacturing Company, 1110., Philadelphia, Pa., a. corporation of Pennsylvania Application November 20, 1946, Serial No. 710,978

2 Claims. (01. I'm-+328) I vention is to provide a lamp socket for fluorescent and other such tubular lamps which, adequately and securely holds the lamp in position against accidental displacement from the socket, the latter characterized by the provision of specially formed spring contacts designed for such beacti'on with the terminal pins of the lamp that jarring of the lamp from the socket, as by vibration or other such shock, is virtually impossible.

A further object of the present invention is to provide a lamp socket of the character described having an entrance slot and recess for the terminal pins of the lamp which permit read-y placement of the terminal pins in operative contact with the spring contacts of the socket While, at the same time, preventing displacement of the pins from the socket except by manual manipulation of the pins within said recess relatively to said spring contacts; the general arrangement being such that in order to effect removal of the lamp from the socket one or the other of the terminal pins oflthe lamp is first required to be rotated out of engagement with its cooperating contact spring of the socket so as to permit the-lamp to be shifted free of both springs for final removal from the socket by way of said entrance slot.

In addition to the foregoing, it is among the objects of the present invention to provide a socket which is readily adaptable for use with the conventional types of tubular lamps now in general commercial use, which is simple in desi n and inexpensive to manufacture and which minimizes breakage of lamps due to difficulties encountered in inserting the same in and removing them from conventional sockets.

Other objects and advantages of the invention will be apparent hereinafter, it being understood that the present invention consists substantially in the combination, construction, arrangement and relative location of parts, as described in detail hereinafter, as shown in the accompanying drawings and as finally pointed out in the appended claims. v

In the accompanying drawings,which are illustrative of a preferred form of a lamp socket constructed in accordance with and embodying the principles of the present invention:

Figure 1 is a front elevational view of the socket;

2 Figure 2 is a vertical sectional view taken on theline 2-2 of Figure 1;

Figure 3 is a rear elevatiohal View thereof; Figure 4 is a transverse sectional view taken on the line 4-4 of Figure 2; I

Figure 5 is a fragmentary frdnt elevational view shbwing the lamp terminal pins in final position within the socket; and

A Figures 6 to 8, inclusive, are fragmentary front elevat io'nal views illustrating successive steps in the entry and engagement of the lamp terminal pins in the socket.

, Referring now to the drawings and more particularly to Figures 1 to 4 thereof, it will be observed that the socket, as constructed in accordance with and embodying the principle's of the present invention, is preferably molded of as'ingle piece of electrical insulating material forming a main body portion l0 having a smooth -surfaced "front face 1 l and a recessed back I 2, the recessed back being provided with a centrally disposed longitudinally extending rib ['3 to provide a pair of laterally spaced recesses I4--l'4 for respective accommodation therewithin of a pair of spring contact members l'5l5.

, Formed as an integral part of the body IQ of the socket at one end thereof is an enlarged part l6 constituting a base for the socket, the rear of this base portion being also recessed as at ll-ll i continuation of the recesses 1 4- a respectively, the recesses IT-H being each of Sufficient width and depth to accommodate therein the terminal end [8 of each springcont'act member l5. These base portions ls-fa "or the sprir'l'g contact members are each provided -with threaded apertures for reception of suitable terminal screws |9- |e by means of which the eleetifical conductors are connected to the contact member. Any suitable means may beprovided for securing the terminalends l8 l'8 of the spring contact members within their respective recesses l'i-l I, it being preferred for this pur'pose to provide the outer walls of the recesses l'lll with grooves 28-2B for receiving the outer edges of the terminal ends I8l8 of the spring, contact members l5-l5. Fitted overthe back of the socket is a back cover element 21 of insulating material suitably secured in position by means of screws 22 received in th-readedapertures 23 23 formed in the central longitudinally extending rib l3, this back cover plate 2| serving conjointly with the integral front surface ll of the socket to house therebetween the spring contact members l5l5. H

Formed in the integral front face member ll of the socket is a heart-shaped opening 23 from the outer end of which extends a communicating slot 2s, said opening 23 and its entrance slot 24 being disposed symmetrically with reference to the longitudinal median plane of the socket. The longitudinal rib I3 is visible to view through said opening 23 and its entrance slot 24, the visible portion of the rib being reduced in thickness to provide a relatively thin septum element 25 dis posed in spaced relation with respect to the apertured front face member II of the socket. Integrally formed upon this septum element 25 is a circular stud 26, the outer end of which is substantially flush with the outer surface of the apertured face member II, the stud being centered within the opening 23 to serve primarily as an element preventing accidental placement of a tool or other device across the contact members ll 5 so as to possibly short-circuit the circuit.

The opposite longitudinally extending sides of the socket are closed by integrally formed walls 27-27 which extend about the outer slotted end of the socket, as at 28-28, to points terminating short of the opposite sides of the entrance slot 24. Preferably, the marginal edges defining the entrance slot 24 in the front face member H are rounded off, as at 2929, for smooth mergence with the opposite basal corners 30-30 of the opening 23.

The spring contact members l5-l5 are each formed of a suitable spring metal, such as fullspring Phosphor-bronze, the blade portions 3 i3l thereof being of substantially straight fiat stock having hook-shaped terminal ends 32-32. The open sides of these terminal ends present generally toward the apex of the opening 23, as shown in the drawings, to respectively receive therein the terminal pins 33-43 of the lamp, the latter being represented in dotted outline in Figures 5 to 8. To properly locate the contact members |5l5 at their extreme outwardly pressed positions when said members are in unfiexed state and free of the lamp contact pins, the recessed back of the socket may be provided with abutments 3 1-34 formed integrally with the side walls 21-21 and spaced from opposite sides of the central rib 13 (see Figure 3), the free ends of these abutments being adapted to serve as fulcrums, respectively, about which the free ends of the contact members may be flexed.

The shape and size of the opening 23 in relation to the distance between centers of the lamp terminal pins is of special importance, it being noted in this connection that while the overall inside dimension of the opening 23 measured along the line a of Figure 5 is somewhat greater than the distance between centers of the lamp terminal pins, the overall inside dimension of said opening measured along the lines b of Figure '7 is even greater. Also, the chordal dimensions of the opening 23, except for that measured along either of the lines b (see Figure 7), are such that when one of the lamp contact pins is seated in one or the other of the hooked terminal ends 32 of the contact members the edge of the opening opposite the seated contact pin is engaged by the other pin and so prevents displacement of the seated pin, such displacement being permitted only when the unseated pin is received within the apex of the opening, this being the only case in which the lamp contact pins may be moved transversely of the lamp axis into the position shown in Figure '7.

To insert the lamp in the socket of the present invention with its terminal pins 33-33 respectively received by the hook-shaped ends of the contact members l5l5, as shown in Figure 5, the lamp is first placed in position with its terminal pins disposed as shown by the dotted lines of Figure 6. The lamp is then shifted upwardly through the entrance slot 24 into the opening 23 with its pins 3333 disposed as shown in full line in Figure 6, following which the lamp is rotated about its axis simultaneously as it is shifted upwardly to present the uppermost pin in the apex of the opening 23 and the lower pin in contact with one or the other of the contact members I5-|5, as shown in Figure '7. The lamp is then dropped to position, the lowermost pin within the hooked end of the contact member (see Figure 8), whereupon upon rotation of the lamp about the fixedly positioned pin as a center the remaining pin may be moved into seated engagement with the hooked end of the other contact member to assume the final position shown in Figure 5. In this latter position, the terminal pins 33-33 will have sprung apart the contact members beyond their normal unfiexed state to thereby insure proper retention of the pins within and electrical contact thereof with the hooked terminal ends of the spring contact members.

As clearly appears from Figure 8, should one or the other of the terminal pins of the lamp become displaced inadvertently from its contact member, due to vibration, shock or other such accident, the lamp will still be retained within the socket by virtue of the fact that the remaining pin remains seated within its associated contact member. Complete removal of the lamp from the socket can only be effected by raising the unsecured terminal pin to a height within the opening 23 sufficient to permit unseating of the other pin from its contact, as shown in Figure '7, and thereafter swinging the latter pin into the position shown in Figure 6 to permit removal of the lamp by an operation the reverse of that described above for insertion of the lamp in the socket.

It will be understood, of course, that the present invention is susceptible of various changes and modifications which may be made from time to time without departing from the general principles or real spirit of the invention, and it is accordingly intended to claim the same broadly, as well as specifically, as indicated by the appended claims.

What is claimed as new and useful is:

1. A socket for tubular electric lamps of the type having spaced contact pins projecting from an end thereof comprising a main body member of insulating material having in one face thereof an opening of cordate shape and an entrance slot extending inwardly from one end of said body member and communicating with the base end of said cordate opening, the marginal edges of the opening defining the opposite basal corners thereof being arcuately shaped to provide opposed notches the mouths of which respectively present inwardly and upwardly toward the center of said cordate opening, the said notch-defining marginal edges of the opening being reversely curved and extended inwardly of the opening at opposite sides of said entrance slot whereby said arcuate notches are respectively outwardly indented relatively to the inner end of said entrance slot, and a pair of spring contact members respectively disposed adjacent opposed side edges of said opening and terminating in arouately-shaped pin-receiving seats presenting inwardl and upwardly toward the center of said cordate opening, said pin-receiving seats of said contact members being respectively disposed by the fact that, except as hereinafter set forth, 5

all of the chordal lines measured from the center of a given arcuate notch to the marginal edges of the cordate opening are of a length less than the overall basal width of said opening, the sole exception being that the chordal lines extending to the region of the apex of the opening opposite the entrance slot thereof are at least equal in length to the overall basal width of said opening.

RUBEN P. ROSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 1 Date 2,261,900 Cavanagh Nov. 4, 1941 2,297,738 Beal Oct. 6, 1942 10 2,407,567 McCarthy Sept. 10, 1947 2,457,780 Levenson Dec. 28, 1948 

